Insulation resistance tester (or high voltage insulation meter) is a special instrument for measuring insulation resistance. It is an ideal test instrument for measuring insulation resistance of large transformers, transformers, generators, high-voltage motors, power capacitors, power cables, arresters, etc. Features: Automatic release voltage function. Suitable for measuring insulation resistance of various electrical equipment and insulating materials such as transformers, motors, cables, switches, electrical appliances, etc. It is suitable for the maintenance, repair, test and verification of various electrical equipment. Rated output voltage variable: The rated output voltage can be switched by the function buttons( 1000V switches between 50V, 100V, 250V, 500V, 1000V) High voltage indication: There is a red LED light in the machine indicating that there is high voltage output in the instrument, there is a danger of electric shock, the operator should pay special attention to safety. Low battery voltage indication. Battery-driven, easier to use. Easy to operate and carry. Strong load capacity, < 1.8 mAh output short-circuit current. Complete conservation circuit, not afraid of voltage counterattack, output short circuit conservation. It can measure AC/DC voltage 10V-600V, AC voltage frequency 40Hz ~ 70Hz. Dust-proof and moisture-proof structure, suitable for outdoor operation. Specifications: Color: Red Material: ABS Batteries Model: 8 * AA batteries (not included) Max. display: 2000 counts Measuring range: 0. 1M~10G Item Size: 172.7 * 140.3 * 62.3 mm / 6.8 * 5.52 * 2.45 inch Item Weight: 621.9g / 21.94oz Package Size: 200 * 180 * 80 mm / 7.87 * 7.09 * 3.15 inch Package Weight: 926g / 32.66oz Package List: 1 * Digital Megohmmeter 2 * Test Cable 2 * Crocodile Clip 1 * Storage Bag 1 * Manual(English)